A false positive on a pregnancy test means that the test detected the hormone hCG in your urine. The newer, more sensitive early pregnancy tests usually detect lower amounts of hCG in the urine, making them more sensitive.
For a false positive to be had, you either have hCG in your body for some other medical reason or the test was not working correctly.
Call your doctor or midwife for advice on what to do, they may with to do blood work to see if hCG is found in your blood.
The other possibility is that you had a correct positive, in that hCG was found, but that the hCG levels are falling. This may be a sign of a miscarriage. Either way, you should call your doctor or midwife for advice. They may be able to use certain treatments like progesterone to save your pregnancy.
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